~ubuntu-branches/ubuntu/trusty/apache2/trusty

                          Apache HTTP Server

  Platform specific notes:

  ------------------------

================

  Darwin (OS X):

   Apache 2 relies heavily on the use of autoconf and libtool to

   provide a build environment.  Darwin provides these tools as part

   of the Developers Tools package. Under Darwin, however, GNUlibtool

   is installed as 'glibtool' to avoid conflicting with the Darwin

   'libtool' program.  Apache 2 knows about this so that's not a

   problem.

   As of OS X 10.2 (Jaguar), the bundled versions work perfectly. Partly

   this is due to the fact that /bin/sh is now 'bash' and not 'zsh' as

   well as the fact that the bundled versions are up-to-date: 

   autoconf 2.52 and (g)libtool 1.4.2.

   Earlier versions of OS X are not so fortunate, and the bundled tools

   are not only older versions, but also, for the most part, do not work

   well.  If you are interested in developing under Darwin, we

   recommend that you obtain and install replacement versions of what

   are normally installed on Darwin (and OS X, as of v10.1.5).  If

   you build your own versions of autoconf 2.52 and libtool 1.4.2, be

   aware that there are some Darwin specific patches to the official

   code that still must be applied for them to fully work.  A useful

   page to check out is:

      http://fink.sourceforge.net/doc/porting/libtool.php

   Pier Fumagalli also provides pre-built Darwin packages of the

   patched autoconf and libtool suites, available at:

      http://www.apache.org/~pier/macosx/

   You will note that GNU libtool should actually be installed as

   glibtool, to avoid conflict with a Darwin program of the same

   name.  Pier's packages have this change already.  All files are

   installed under /usr/local/ so to use these versions, and be sure

   that /usr/local/bin is earlier in your PATH.

   There have been some reports that autoconf 2.52 prevents Apache's

   build system from correctly handling passing multi-value envvars

   to the build system (eg: CFLAGS="-g -O3" ./configure),  causing

   errors.  Use of bash does not seem to help in this situation.  If

   this affects you, downgrading to autoconf 2.13 (which is installed

   on Darwin) will help.

   With Leopard (at least up to 10.5.2), when running configure

   you will likely see errors such as:

      rm: conftest.dSYM: is a directory

   This is a known issue and will be fixed in a later version of the

   autoconf suite. These errors can be safely ignored.

   With Darwin 10, the default C compiler (gcc) will try to build

   multi-architecture bundles. This causes problems with APR, which

   needs to know various data-type sizes which it assumes are universal

   for platforms. Until this is fully fixed, we recommend using the

   '-arch i386' gcc option when building both Apache and APR.

==========

  FreeBSD:

   autoconf 2.52 creates scripts that are incompatible with the Posix

   shell implementation (/bin/sh) on FreeBSD.  Be sure to use v2.13

   of autoconf.

   Threaded MPMs are not supported on FreeBSD 4.x.  Current releases of

   FreeBSD 5.x (5.2 or later) support threaded MPMs correctly.  You must pass

   '--enable-threads=yes' to APR's configure in order to enable threads.

   Additionally, you must use libthr or libkse via libmap.conf as the default

   libc_r is still broken as of this writing.  Please consult the man page for

   libmap.conf for more details about configuring libthr or libkse.

================

  HP-UX:

   The dlopen() system call in HP-UX has problems when loading/unloading

   C++ modules. The problem can be resolved by using shl_load() instead

   of dlopen(). This is fixed in the Apache 2.0.44 release.

   To enable loading of C++ modules, the httpd binary has to be linked with

   the following libraries :

   HP-UX (11.0 / 11i):

      When using shl_load        : "cpprt0_stub.s -lcl"

      When using dlopen          : "cpprt0_stub.s -lcl -lCsup"

   HP-UX (11i version 1.5 and greater):

      When using dlopen/shl_load : "cpprt0_stub.s -lcl -lunwind"

   The cpprt0_stub.s can be downloaded from the web site :

      http://h21007.www2.hp.com/hpux-devtools/CXX/hpux-devtools.0107/0083.html

   Compile cpprt0_stub.s with the PIC option

     cc -c +z cpprt0_stub.s

       - OR -

     gcc -c -fPIC cpprt0_stub.s

================

  AIX, using the vendor C compiler with optimization:

    There is an issue with compiling server/core.c with optimization enabled

    which has been seen with C for AIX 5.0.2.3 and above.  (5.0.2.0, 5.0.2.1,

    and 5.0.2.2 have an additional problem with Apache 2.0.x, so either upgrade 

    the compiler or don't use optimization in order to avoid it.)

    cc_r works fine with -O2 but xlc_r does not.  In order to use xlc_r with

    -O2, apply the patch at 

    http://www.apache.org/dist/httpd/patches/apply_to_2.0.49/aix_xlc_optimization.patch

    (That patch works with many recent levels of Apache 2+.)

================

  Solaris:

    On Solaris, better performance may be achieved by using the Sun Studio

    compiler instead of gcc.  As of version 11, it is now free (registration

    required).  Download the compiler from:

    http://developers.sun.com/prodtech/cc/downloads/index.jsp

    If you use Sun Studio, the following compiler flags (CFLAGS) are

    recommended:

      -XO4 -xchip=generic